Răspuns:
10 x + y + 10 y+ z + 10 z + x = 121
11 x+ 11 y + 11 z = 121
11 × ( x + y + z) = 121
x + y + z = 121:11
x + y + z = 11 si x < y < z
1 + 2 + 8 = 11 ; 1 + 3 + 7 = 11 ; 1 + 4 + 6 = 11; 2 + 3 + 6 = 11; 2 + 4 + 5 = 11
Deci numerele de forma xyz in baza 10 stiind ca xy + yz + zx = 121 si x<y<z sunt : 128, 137, 146, 236, 245
